Preparation of SiC Ultrafine Particles by Using CO₂ Laser

Abstract

Preparation of SiC ultrafine particles from SiH₂Cl₂-C₂H₄ mixtures by using CO₂ laser was investigated. Powders with specific surface areas of 8 to 150m²/g, were obtained by irradiating CO₂ laser beam to SiH₂Cl₂-C₂H₄ gas mixture at atmospheric pressure. The power density of laser beam was 3.66kW/cm² and wave length was 10.6μm. XRD of the products showed that Si, β-SiC and free carbon were produced and that the composition of powders depended on the C₂H₄/SiH₂Cl₂ ratio. Reaction temperature changed with the power density of laser beam and C₂H₄/SiH₂Cl₂ ratio. Hysteresis was observed between reaction temperature and power density of laser beam.